INTRODUCTION
Congenital lobar emphysema (CLE) also known as congenital lobar overinflation, is a rare developmental lung malformation. The respiratory system begins to develop during the third week of pregnancy, and developmental anomalies during this stage can lead to parenchymal lung malformations (1-3). CLE is the hyperaeration of one or more lung lobes due to partial obstruction (4) and occurs at a rate of 1/20,000–30,000 live births. CLE is more common in male infants but rarely causes respiratory distress in newborns (5-7). The diagnosis can be performed with ultrasonography at various stages of the pregnancy (8). Approximately half of the patients with CLE are symptomatic at birth, and most are diagnosed within the first 6 months of life (9-11). The most affected lobes are the left upper lobe, right upper lobe, and right middle lobe. Involvement of the lower lobes and more than one lobe is very rare (9-13). Pathology samples typically show no tissue damage, except for acquired emphysema and the occasional accompanying cartilage hypoplasia. Acinar and alveolar structures are both normal in CLE; however, the alveoli can experience secondary hypertrophy, and the affected lung tissue cannot postnatally mature (9). Bronchial collapse develops due to structural damage in the bronchial wall and can cause distal air trapping on expiration (14). The etiology of CLE can include hypoplasia, dysplasia, and the absence of primary or secondary bronchial cartilage; however, most of these conditions are idiopathic. CLE can be observed as the result of congenital bronchial diseases such as primary bronchial stenosis/atresia and bronchomalacia. Secondary causes of CLE include meconium aspiration and the obstruction of mucous plaques and membranes (15-17). Although rare, bronchogenic cysts and mediastinal masses have also been shown to cause CLE (18). The progressive increase in ventilation can also result in compression of adjacent organs and, rarely, impaired perfusion. Substernal and subcostal retraction, wheezing, cyanosis, and feeding difficulties can occur during the neonatal period, whereas chronic cough and frequent lung infections can occur during infancy and might be difficult to distinguish from foreign body aspiration (9).
During bronchial development, as cardiac structures develop between 4 and 6 weeks of pregnancy, CLE can also be accompanied by congenital heart diseases (CHDs), such as patent ductus arteriosus, atrial septal defect, ventricular septal defect, total anomalous pulmonary venous drainage, and tetralogy of Fallot at varying rates. External compression of vascular structures can sometimes be the cause of secondary CLE (19). Hyperechogenicity, mediastinal shift, and polyhydramnios can be observed through intrauterine ultrasonography of the lung structures, with normal blood flow (20-23). During the postnatal period, the first choice for diagnosis is chest radiography (CXR), which can reveal increased aeration in the affected lobe. In severe cases, the CLE might be accompanied by herniation of the opposite lung (9). Thoracic computed tomography (CT) performed with contrast provides more detailed information on vascular compression, endobronchial occlusive masses, bronchial atresia, etc., in elucidating the causes and differential diagnosis. Anatomical anomalies such as bronchial atresia, bronchomalacia, mucus plaques, and mucosal flaps can be observed with flexible bronchoscopy (FB). Suspected foreign body aspiration can also be ruled out with FB (23).
Treatment decisions are reached according to clinical, radiological, and bronchoscopy findings. When the symptoms and signs are mild to moderate, when the patient’s growth and development are not affected, and when there is no accompanying respiratory distress, a conservative approach is adopted. Lobectomy is recommended only for patients with severe and progressive findings (23). Close follow-up is recommended for patients for whom a conservative approach is advised, given that the clinical findings can progress at later ages and that surgery might be required (5).
The aim of this study is to retrospectively examine the clinical, radiological, and bronchoscopy findings of patients diagnosed with CLE in our clinic who are followed up with conservative and/or surgical approaches and to compare our results with those in the literature.